As shown in FIG. 1, in a conventional liquid crystal display device or an organic light emitting diode (OLED) display device, each point (pixel 2) displays a color by means of mixing light via a first color sub-pixel 11, a second color sub-pixel 12 and a third color sub-pixel 13. For example, each pixel 2 comprises (RGB mode) one red sub-pixel, one green sub-pixel and one blue sub-pixel. To improve the visual effect, people propose higher and higher requirements on the resolution (the number of pixels per unit size) of a display device, which requires that sizes of the sub-pixels become smaller and smaller. However, the sizes of the sub-pixels could not be unlimitedly decreased due to process limit.
In order to improve the display effect in a condition that sizes of sub-pixels are fixed, a display device of a Pentile mode has been provided. In the display device of the Pentile mode, the number of sub-pixels (such as red sub-pixels and blue sub-pixels) of some color(s) is halved; meanwhile, in the display device, different colors of sub-pixels are virtually considered as being located in different “layers”, and each layer is divided into a plurality of sampling areas, and the divisions of the sampling areas of the layers are not overlapped, and then, contents to be displayed by each sub-pixel are calculated through the area ratios of the sampling areas. In the display device of the Pentile mode, a part of sub-pixels are “common”, thus visually achieving a resolution higher than the actual resolution.
However, the display effect of the existing display device of the Pentile mode is still not ideal, as the number of the sub-pixels of some color(s) is halved, the sub-pixels of various colors are not evenly distributed, which leads to such problems as easy occurrence of jagged lines, grid spots, unclear display of fine contents, and the like; meanwhile, since the calculation mode based on “layer and partition” is adopted, a complicated calculation process is needed for calculating the contents to be displayed by each sub-pixel, such that the calculation amount is large.